My husband has squamous cell carcinoma of the metastatic spindle variety. He had been on centuximab (Erbitux) starting in September 2016. It worked well for the cutaneous tumors, but in May 2017 PET scan showed three tumors on the liver, diaphragm and the spine at the base of the neck. Immediately began Keytruda and the October 2017, plus the results of the January 2018 PET scan were clear of any visible cancer.
He continues to suffer great fatigue, which I believe to be the result of radiation Feb-Apr 2017. However, he is able to work part time. There are no side effects which we can pin exactly on the Keytruda.